class_docstr: A query that matches per-document values stored in a column rather than
  terms in the inverted index.
  
  This may be useful in special circumstances, but note that this is MUCH
  SLOWER than searching an indexed field.
class_docstr_tok: ["A","query","that","matches","per-document","values","stored","in","a","column","rather","than","terms","in","the","inverted","index",".","This","may","be","useful","in","special","circumstances",",","but","note","that","this","is","MUCH","SLOWER","than","searching","an","indexed","field","."]
docstr: :param fieldname: the name of the field to look in. If the field does
      not have a column, this query will not match anything.
  :param condition: if this is a callable, it is called on each value
      in the column, and for documents where callable(docvalue) returns
      True are returned as matching documents. If this is not a callable,
      the document values are compared to it (using ``==``).
docstr_tok: [":","param","fieldname",":","the","name","of","the","field","to","look","in",".","If","the","field","does","not","have","a","column",",","this","query","will","not","match","anything",".",":","param","condition",":","if","this","is","a","callable",",","it","is","called","on","each","value","in","the","column",",","and","for","documents","where","callable","(","docvalue",")","returns","True","are","returned","as","matching","documents",".","If","this","is","not","a","callable",",","the","document","values","are","compared","to","it","(","using","``","==","``",")","."]
code: def __init__(self, fieldname, condition):
      """
      :param fieldname: the name of the field to look in. If the field does
          not have a column, this query will not match anything.
      :param condition: if this is a callable, it is called on each value
          in the column, and for documents where callable(docvalue) returns
          True are returned as matching documents. If this is not a callable,
          the document values are compared to it (using ``==``).
      """
  
      self.fieldname = fieldname
      self.condition = condition
  
file_path: whoosh/src/whoosh/query/qcolumns.py
imports: from whoosh.matching import ConstantScoreMatcher, NullMatcher, ReadTooFar
  from whoosh.query import Query
label_desc: Use image node_id 1 to create a new ColumnQuery object from inherited base classes: Query with example: obj = ColumnQuery(fieldname, condition)